背景：當option特別多時，一般的下拉框選擇起來就有點力不從心了，所以使用multiselect是個很好的選擇，可以通過輸入文字來選擇選項很方便，但是有一個需要下拉框聯動，網上找了半天才找到解決方法，在此分享一下

1、先引入

<script src="~/Assets/js/bootstrap-multiselect.min.js"></script>  <link href="~/Assets/css/bootstrap-multiselect.css" rel="external nofollow" rel="stylesheet" />

然后全局定義

 function RegSelect() {      $('.multiselect').multiselect({        buttonClass: 'btn btn-white ',        enableFiltering: true,        enableHTML: true,        includeSelectAllOption: true,        selectAllText: '全選',        allSelectedText: '全部選中',        nonSelectedText: '請選擇',        nSelectedText: '個被選中',        templates: {          button: '<button type="button" class="multiselect dropdown-toggle" data-toggle="dropdown"><span class="multiselect-selected-text"></span>  <b class="fa fa-caret-down"></b></button>',          ul: '<ul class="multiselect-container dropdown-menu"></ul>',          filter: '<li class="multiselect-item filter"><div class="input-group"><span class="input-group-addon"><i class="fa fa-search"></i></span><input class="form-control multiselect-search" type="text"></div></li>',          filterClearBtn: '<span class="input-group-btn"><button class="btn btn-default btn-white btn-grey multiselect-clear-filter" type="button"><i class="fa fa-times-circle red2"></i></button></span>',          li: '<li><a tabindex="0"><label></label></a></li>',          divider: '<li class="multiselect-item divider"></li>',          liGroup: '<li class="multiselect-item multiselect-group"><label></label></li>'        }      });    }

只需要在頁面加載時RegSelect();（只能調用一次，不然會出現問題）就可以了

2、兩個下拉框

 <div class="form-group">          <label for="RepairOrg" class="col-sm-3 control-label">維修單位</label>          <div class="col-sm-9">            @Html.DropDownList("RepairOrgUID", ViewBag.OrgList as List<SelectListItem>, "請選擇", new { @class = "form-control multiselect", onchange = "OrgChange(this)", id = "RepairOrg" })          </div>        </div>        <div class="form-group">          <label for="RepairContact" class="col-sm-3 control-label">維修人</label>          <div class="col-sm-9">            @Html.DropDownList("RepairContactUID", ViewBag.ContactList as List<SelectListItem>, "請選擇", new { @class = "form-control multiselect", id = "RepairContact" })          </div>        </div>